Refrigerating system



A. C. SCHICKLER Oct. 6, 1931.

v REFRIGERATING SYSTEM 2 Sheets-Sheet 1 Filed Nov. 15, 1926 Oct. 6, 1931.

A. C. SCHICKLER REFRIGERATING SYSTEM Filed Nov. 15, 1926 2 Sheets-Sheet 2 Patented a. 6,1931

ALBERT c. scmcxnxa, or

CLEVELAND, OHIO, ASSIGNOB TO EDMUND mm 0] CLEVELAND, OHIO BEFRIGERATING SYSTEM Application 11m Rovember 15,1920. Serial 110. 148,501.

This invention relates to refrigerating apparatus of the absorption type, where a suitable refrigerant, such as ammonia, is distilled in a boiler from a suitable absorbing agent, such as water, is condensed and delivered to an evaporator, and then, during the second phase of the cycle, is evaporated, in.

the evaporator to produce a refrigerating effeet and is returned to and absorbed in the liquid absorbing agent-in the boiler, which now serves as an absorber.

In suchsystems one objection has been the undesirable transfer of heat to the refrigerating chamber during the boiling operation by the refrigerant delivered to the evaporator. Also, in absorption systems of the reversed cycle type, employing a so-called thermo-siphon cooling system for the stillabsorber, the gas returning to the still usually has passed through the .condenser, now subjected to the influence of the heated water delivered to it from the still-jacket, with a consequent undesirable rise in temperature of the returning gas and decreasing efiiciency in the absorbing operation.

The present invention has for its object to provide an improved refrigerating system of the absorption type. and particularly an intermittent system with a reversible heating and'refrigerating cycle, in which the system is closed or sealed fromthe. atmosphere with no possible leaks or avenues of escape, in which the distilled and condensed refrigerant is collected in areceiver and cooled before delivery to the evaporator early in or during the refrigeratingoperation, with the possibility of shielding the refrigerating chamber from the effects of heat otherwise transferred to it; in which the refrigerant, during distillation and condensation, travels by one path from the still to the evaporator,

and during refrigeration travels by another path in thereverse direction and particularly a path, which avoids or by-passes the condenser or receiver or both; and finally in which control of the circulation of refrigeram is efiected by hydrostatic seals which opcrate efficiently and without attention and are not likely to get out of order in service.

A further object is to provide a self-com tainedsystem sealed against any possible escape of refrigerant and capable of complete inversion during shipping or handling, in which event its restoration to normal upright position restores all parts, including refrigerant, absorbing agent, and sealing means or 'devlces, to their proper worklng condition and does not interfere with correct operation.

A flu'ther object of the invention is to pro- 'vide an improved hydrostatic seal or trap for controlling the flow' of refrigerant from and to the still, directin it. by the easiest path in both directions an upon its return to the still supplying the gas below the surface of the absorbing agent to promote absorption therein.

A further object of the invention is to provide an improved form of hydrostatic seal, and particularly a mercury seal, which is of simple construction and avoids any possible escape of the sealing liquid to other parts of the apparatus, and, further, a hydrostatic seal of the unbalanced type, ofi'ering greater resistance to flow therethrough in one direc tion than in the other and thereby serving in effect as a check valve.

Further objects of the invention are in part obvious and in part will appear more sectional elevation, on a larger scale, illustrating one of the hydrostatic seals; and Fig. 7 1s a diagram showing modifications.

- For convenience. the invention has been shown in Fig. 1 in one of its simpler ,forms,

embodying'a still-absorber 1, a condenser including either or both of the coil 2 and re- The drawings. show four hydrostatic seals,

marked respectively 6, 7, 8 and 9, of which the seals 6, 7 and 8 may be alike as to form, possibly differing only insize or proportions or quantities of seahng liquid, so that description of one will sufiice for all, while the seal 9 is slightly modified to serve as a trap for the passage of the refrigerant to and from the still-absorber. Forcooling purposes the still-absorber is jacketed, as at 10, the chamber 11 within the jacket being connected at upper and lower levels by pipes 12, 13, the former valved as at 14, to the chamber or reservoir 15 of the condenser, the still jacket and said reservoir, together with the circulation pipes 12, 13, serving as a thermosiphon cooling system for the boiler. The receiver 3 may be located in the chamber, of reservoir 15, in which case coil 2 may be omitted, as shown in Fig. 7, and the receiver alone may be the condenser,.but, as shown in Fig; 1, said .receiver is located in a chamlated through the boiler, it being understood voir 4, the

that both chambers 15, 15a are so constructed and arranged as to gradually radiate their heat to the surrounding air or other cooling medium. q

. Gas distilled from the still 1 is carried by the pipe 17 to the point 18 from which two pipes lead, one to the hydrostatic seal 6 and the other to the seal 7. The first seal 6 prevents flow through the branch19 to the resergas being compelled to flow through the seal 7 to the condenser, in which the condensed refrigerant collects in receiver 3, and is held as a liquid during the distilling operation. During distillation valve 14 is closed, so that no circulation of cooling water occurs in the thermo-siphon coolingsystem.

erating chamber and serve as the evaporator or apart thereof, but is preferably confined or shielded in a restricted portion ofthe refrigerating chamber-by walls of good heat insulating material, so that the reservoir 4 serves mainly for storage of refrigerating liquid, delivering the same by gravity to the refrigerating coils or bends of pipe 5 exposed in the refrigerating chamber.

The gas distilled during refrigeration leaves the top of reservoir 4through pipe 19 and passes through the h drostatic seal 6 tothe pipe 17 and to the boi er.

Any absorbing agent, such as water, carsorbing agent collected 1n said pipe flows by gravity past the seal 8 and is returned to the boiler, this return pipe for absorbing agent and its hydrostatic seal operatingas described in my prior application for refrigcrating system, filed October 27, 1926, Ser.

No. 144,461, to which reference may be had for a-more complete description thereof if necessary.

Any or all of the several seals 6, 7 and 8 may be of the general form shown in my prior application referred to, or of the improved form shown in detail in Fig. 6. This seal includes a reservoir containing a suitable quantity of sealing, agent having a density greater than that of the refrigerant of absorbing agent and unaffected by either thereof or by the metal walls of the system, and producing no effect upon them, one suitable substance for the purpose being mercury, with a density of 13.6 as compared with a densityof 1.0 for water and of approximately .8 for ammonia solutions. A column of mercury therefore will balance a column of waterior ammonia about fourteen times its own height and a proper hydrostatic seal employing mercury can be made of comparatively small dimensions. The seal is of the U-tube type with its two. legs connected'one to the inlet and the other to the outlet pipe. The mercury reservoir is a cylindrical metal vessel 23 of say two inches in diameter, the

inlet pipe, marked24 in Fig. 6, coming in from above endwise along its axis and extending to the bottom of the chamber, where the pipe is notched at two sides, as at 24a, forming two end legs 24?) which may be welded or. otherwise secured to the bottom wall and which provide two small ports or openings at the recesses 24a from the channel of pipe 24 to the chamber in the vessel. The outlet pipe 25 extends horizontally through a side wall of the vessel and at its inner open end is quite close to the center of the vessel and abuts the side of the inlet pipe 24, to which it may be welded or otherwise secured, as shown in Fig. 3. This arrangement provides two small semi-circular openings 27 from the channel in pipe 25 to the chamber within the vessel. The mercury in the vessel is of such quantityjthat when pressures are equalized on opposite legs it stands at a level a little above the upper edges of the openings 24a.

With such an arrangement the two mercury legs are located respectively, one Withproperly proportionin teac es in tube 24 and the other within the chamber of vessel 23, the former being of smaigross chamber 23 causes the mercury in pipe 24 to climb to such a height that the maximum differential in height between the legs of the U-tube is much greater. Therefore, by the'cross sectional areas of the pipe 24 an vessel 23 and charg ing said vessel with the proper quantity of mercury, and by connecting the seal in the" conduit in the proper direction, resistances to flow in the two directions. in any desired amounts may be secured. In other words, the'resistance to flow in one direction may be made the same as that in the other, or, the resistance to flow in either direction may be made greater than the resistance in the other direction and in any desired amount, and each seal is proportioned and is charged with mercury according to the requirements of its special duty.

Considering now the two seals 6 and 7, it Will be noted from Fig. 1 that they are'so connected that during boiling the ga s flowing from the still finds greater resistance to flow through the seal 6 than through the seal 7 Consequently it flows through the later seal and to the condenser-and receiver and thence, later, to the reservoir 4. During refrigeration the gas returning to thestill from the evaporator finds greater resistance to flow at the seal 7 than at the seal 6,'so that it returns through seal 6.

While it may be true, that in these systems 7 there is no sharp line of demarcation be.-

tween anhydrous ammoniaor refrigerant on the one hand and water or absorbing agent on theother, yet it is true that the greater the proportion of Water in the mixture the heav ier 'it'is, and for purposes of discussion we say the line A, Fig. 1. This maintains serviceable or valuable strong refrigerating a-mmonia above said level and in the coils 5. At anytime, during either boiling or refrigeration, when weak solution delivered to the evaporator rises above the level A the weight of the leg of liquid in the pipe 22 will be greater than the maximum mercury leg in the boiler side of the seal 8 and the weak solution flowsback through said seal to the boiler.

The trap 9 is for the purpose of introducing the returning gas below the surface of theabsorbing agent. It is not essential, as

-.will' a pear. It includes a pipe 30 coming from t 0 top of the boiler and entering-the top, of the mercury vessel or re eiver, said pipe extending to the bottom of the vessel in the samemanner'as the inlet pipe 24, Fig. 6. The pipe 17 enters the top of the vessel and vextends down to about its middle where it abuts the end of a pipe 31 leading downwardly to the bottom of the still where it is laterally extended and provided with a series of small openings 32 to distribute the gas. The two pipes 31 and 17 are separated by a cross wall 33 and each is provided'with one or several small openings 34, said openings being above the normal level of mercury, and all of the pipes 17,30 and 31 are near the central axis of the mercury vessel. This trap offers an easy path for escape of the gas toward the condenser during boiling but delivers it to the absorbing agent below its .upper surface.

It will be noted that all of the mercury containing vessels are of a character preventing m'ercurv escape to other parts of the apparatus. Considering the vessel shown in its normal operative position in Fig. 6, it will be noted that if said vessel is rotated about an axis perpendicular to the plane of the drawing at say the point marked B, the mercury leaves the openings 24a before the pipe- 24 becomes even slightly inverted; Furthermore, the upper surface of the mercury never reaches the openings 27 and pipe 25 may be protected or bafiled not only by the pipe 24 but also, if desired, by the washers or rings 240. Therefore, inversion of the apparatus or one of these seals cannot cause the escape of mercury. Y

, As an additional safeguard, however, either or both of the pipes 24, 25 may be provided with additional mercury escape preventing means, such as the vessel 35 connected to pipe 24 at one end and at the other end having a portion of the pipe 24 entering the vessel and terminating nearit's' center with its end closed, as at 36, and provided with small ports 37 in its side. This vessel is similar to the wells shown and describedv suitable form and controlled by pressure,

temperature, or levels of liquid in' one or during boiling the distilled gas passes of through the trap 9 to pipe 17, thence to the condenser and receiver3 where it is collected and held. During boiling no circulation of cooling water occurs but the cooling water during the preceding extended refrigerating operation has given up its heat to the surrounding air or other cooling medium and is hence atja temperature suflicient to initiate and promote condensation of the refrigerant. Additional heat of the refrigerant is given up to the non-circulating water trapped in the receiver chamber 15a,'or said receiver may be subjected to the effect of flowing tap water or the like if desired. The boiling operation preferably is initiated before the level of refrigerant in storage vessel 4 has reached its bottom, so that even during boiling the coils 5 remain full of refrigerant. Heat is.

not materially conveyed to the refrigerator coils during the boiling operation, so that its temperature will not rise materially. When the cycle is reversed and the refrigerating operation begins the thermo-siphon valve 1a is opened and a shot of the colder water in chamber 15 flows into the still jacket and the hotv water in the latter flows into chamber 15. Evaporation of refrigerant begins and the charge thereof in vessel 3 is forced over into vessel 4 and coils 5, where the refrigerating operation ,continues, the gas distilled being conveyed by pipes 19 and 17 to' the trap 9 and from the latter by way of pipe 31 to the absorbing agent. During both parts of the cycle any weak solution delivered tothe evaporator flows back by way of pipe 22 and seal 8 to the pipe 31 and thence to the still.

Fig. 7 shows another arrangement of apparatus in which the trap 9 shown in Fig. 1 is omitted and the circulating pipes are arranged in a different manner for delivering the returning gas to the absorber beneath the level of the absorbing agent. In this case the gas distilled in the boiler 1 passes off by way of pipe 17 and seal 7 to the condenser receiver 3, no condenser coils being shown although they may be used if desired. The liquid inboiler 1 is held back from entering the pipes 19, 22 by the seals 6, 8, both commu-.

heavier liquid draining back to the boiler through the pipe 22 and seal 8 as before. The gas distilled in the evaporator rises to the top of reservoir 4 and returns to the boiler by way of pipe 19 and seal 6, thence through the pipe 31 .to the outlets 32 at a low level in the absorbing agent.

The two seals, 7, 8 are essential, the first to-form a check valve to trap pressure for driving the charge from the receiver to the absorber and the second 8, to hold its column of liquid in the pipe 22. The seal 6 is not always essential and in some cases may be omitted. due to the fact that the evaporator 4'is frequently located at a fairly high level, say four or five feet, above the boiler 1, and the head of liquid raised in pipe 19 may itself be sufiicient to prevent the liquid, during boiling, from being forced over to the evaporator 4 byway of pipe 19. Even should some liquid reach the evaporator by this path, it would return to the boilerby way of the pipe 22. y

What I claim is 1. Refrigerating apparatus of the intermittent absorption type, including a stillabsorber, a receiver and an evaporator connected in the order named, a return gas conduit from the evaporator to the still-absorber, and liquid sealing means between the stillabsorber and recelver arranged to permit unimpeded collection of liquid refrigerant in the receiver during boiling and to cause movement of the same into the evaporator during refrigeration, said sealing means being unaffected by inversion of the apparatus.

2. Refrigerating apparatus of the intermittent absorption type, including a stillabsorber, a receiver and an evaporator connected in the order named, a return gas conduit from the evaporator to the still-absorber,

and liquid sealing means between the still-' absorber and recelv'er arranged to permit unimpeded collection of liquid refrigerant in the receiver during boiling'and to cause movement of the same into the evaporator during refrigeration, said sealing means being provided with means for preventing escape of sealing liquid to other parts of the apparatus. s

3. Refrigerating apparatus of the intermittent absorption type, including a still-absorber and an evaporator, communicatingconduits between them including an outlet from the gas spacein the still and an inlet below the liquid level therein; and liquid sealing means compelling unidirectional flow through said conduits, said-sealing means being unaffected by inversion of the apparatus.

4. Refrigerating apparatus of the intermittent absorption type, including a still-absorber, a receiver and an evaporator, conduits connecting them in the order named and including a return gas conduit from the evaporator to the still-absorber and liquid sealmg means between the still and receiver,

whereby to collect a charge of refrigerant in the receiver during boiling and to cause transfer thereof to the evaporator during refrigeration.

5. Refrigerating apparatus of the intermittent absorption typeincluding a still-absorber, a condenser, and an evaporator connected in operative cycle, liquid sealing means for directing the gas in its proper course through said apparatus during the several cycles of operation, and means in said apparatus, normally ineffective upon the,

ranged upon inversion of the apparatus to prevent the escape of sealing li uid from the sealing point to other arts of t e apparatus and upon restoration 0 the apparatus to normal position to return the sealing liquid to said outlet and return during 0 sealing condition.

7, Refrigerating apparatus of the intermittent absor tion type including a still-absorber, a con enser, and an evaporator, conduit means for connecting them in an operative cycle and including a separated gas outlet and gas return to the still-absorber liquid sealing means for directing the gas t rou h ration oft e apparatus, and means for retaining the sealing liquid in saidsealing means in s ite of inversion of the apparatus and return t y e sealtionof the apparatus to normal'position. i

In testimony whereof I hereby aflix my ing liquid to the sealing means on the restorasignature.

. ALBERT C. SCHICKLER. 

